Answer:
(a) The resistor disspates 103680 joules during a 24-hour period.
(b) The heat flux of the resistor is approximately 4340.589 watts per square meter.
(c) The fraction of heat dissipated from the top and bottom surfaces is 0.045.
Explanation:
(a) The amount of heat dissipated ([tex]Q[/tex]), measured in joules, by the cylindrical resistor is the power multiplied by operation time ([tex]\Delta t[/tex]), measured in hours. That is:
[tex]Q = \dot Q \cdot \Delta t[/tex] (1)
If we know that [tex]\dot Q = 1.2\,W[/tex] and [tex]\Delta t = 86400\,s[/tex], then the amount of heat dissipated by the resistor is:
[tex]Q = (1.2\,W)\cdot (86400\,s)[/tex]
[tex]Q = 103680\,J[/tex]
The resistor disspates 103680 joules during a 24-hour period.
(b) The heat flux ([tex]Q'[/tex]), measured in watts per square meter, is the heat transfer rate divided by the area of the cylinder ([tex]A[/tex]), measured in square meters:
[tex]Q' = \frac{\dot Q}{A}[/tex] (2)
[tex]Q' = \frac{\dot Q}{\frac{\pi}{2}\cdot D^{2}+\pi\cdot D \cdot h }[/tex] (3)
Where:
[tex]D[/tex] - Diameter, measured in meters.
[tex]h[/tex] - Length, measured in meters.
If we know that [tex]\dot Q = 1.2\,W[/tex], [tex]D = 4\times 10^{-3}\,m[/tex] and [tex]h = 2\times 10^{-2}\,m[/tex], the heat flux of the resistor is:
[tex]Q' = \frac{1.2\,W}{\frac{\pi}{2}\cdot (4\times 10^{-3}\,m)^{2}+\pi\cdot (4\times 10^{-3}\,m)\cdot (2\times 10^{-2}\,m) }[/tex]
[tex]Q' \approx 4340.589\,\frac{W}{m^{2}}[/tex]
The heat flux of the resistor is approximately 4340.589 watts per square meter.
(c) Since heat is uniformly transfered, then the fraction of heat dissipated from the top and bottom surfaces ([tex]r[/tex]), no unit, is the ratio of the top and bottom surfaces to total surface:
[tex]r = \frac{\frac{\pi}{2}\cdot D^{2}}{A}[/tex] (3)
If we know that [tex]A \approx 2.765\times 10^{-4}\,m^{2}[/tex] and [tex]D = 4\times 10^{-3}\,m[/tex], then the fraction is:
[tex]r = \frac{\frac{\pi}{2}\cdot (4\times 10^{-3}\,m)^{2} }{2.765\times 10^{-4}\,m^{2}}[/tex]
[tex]r = 0.045[/tex]
The fraction of heat dissipated from the top and bottom surfaces is 0.045.
A 0.500 cm diameter plastic sphere, used in a static electricity demonstration, has a uniformly distributed 44.0 pC charge on its surface. What is the potential near its surface
Answer:
Explanation:
Radius of sphere R = .250 x 10⁻² m
Potential on the surface V = k Q / R , where Q is charge on the surface , R is radius of the surface and k = 9 x 10⁹
Q = 44 x 10⁻¹² C
V = 9 x 10⁹ x 44 x 10⁻¹² / ( .25 x 10⁻²)
= 1584 x 10⁻¹ Volt .
= 158.4 Volt
Please answer the question
Answer:
D
Explanation:
He walked a shorter distance, she walked a longer distance but got that wing thingies
What are used to measure temperature.
Answer:
A thermometer is an instrument that measures temperature.
Explanation:
PLEASE HELP! THIS IS TO BE TURNED IN IN ABOUT 3 MINUTES!!!!!!!
How must the net force be acting on an object in order for the object to have a circular motion? What is this type of force called?
3. A car has a mass of 1,000 kilograms. If a net force of 2,000 N is exerted on the car, what is its acceleration?
Answer:
2 m/s^2
Explanation:
Acceleration = Force/mass
= 2,000/1,000
= 2
Why can’t a real machine ever have 100% efficiency
Answer:
Almost all machines require energy to offset the effects of gravity, friction, and air/wind resistance. Thus, no machine can continually operate at 100 percent efficiency.
The nearest neighbor interaction force is of magnitude 481 nanoNewtons, e.g., the magnitude of the force of the leftmost electron on the proton, or the magnitude of the force of any of the three on its nearest neighbor electron. Calculate the size of the net force on the leftmost proton.
Answer:
F = 120.25 10⁻⁹ N
Explanation:
In this exercise, the force between the closest neighbors is indicated by f = 481 10⁻⁹ N, in general between the one-dimensional solid the distances remain the same, if the distance between the first neighbor is d, the distance between the second neighbors is 2d.
For most solids the attractive forces are electrical, therefore force is proportional to the electrical charges and the inverse of the distance squared,
F = [tex]k \frac{q_1 q_2}{r^2}[/tex]
if we call fo the force for the first neighbors
F₀ = k \frac{q_1 q_2}{d^2}
the force for the second neighbors r= 2d
F = k \frac{q_1 q_2}{(2d)^2}
F = F₀ / 4
let's calculate
F = 481 10⁻⁹ / 4
F = 120.25 10⁻⁹ N
Two forces P and Q act on an object of mass 7.00 kg with Q being the larger of the two forces. When both forces are directed to the left, the magnitude of the acceleration of the object is 1.40 m/s2. However, when the force P is directed to the left and the force Q is directed to the right, the object has an acceleration of 0.700 m/s2 to the right. Find the magnitudes of the two forces P and Q .
Answer:
Explanation:
Q is larger than P . When two forces act in the same direction , Resultant force
can be calculated by adding them up . When two forces act in the opposite direction , Resultant force can be calculated by subtracting them .
Force = mass x acceleration .
In the first case
Resultant force = mass x acceleration
P + Q = 7 x 1.4 = 9.8 N
In the second case
Q - P = 7 x 0.7 = 4.9
Adding up these two equations
2 Q = 14.7
Q = 7.35 N
P = 9.8 - 7.35 = 2.45 N .
What does the word quantum mean?
Answer:
a required or allowed amount, especially an amount of money legally payable in damages.
OR
In physics it means a discrete quantity of energy proportional in magnitude to the frequency of the radiation it represents.
Explanation:
Do You think History is the most important subject that deserves first place? Do you see a way that learning history could assist you in your future career?
yes
Explanation:
history is an important class and it helps to you understand what went on in the past so that we can learn from our mistakes and help us grow
A 7300 kg rocket blasts off vertically from the launch pad with a constant upward acceleration of 2.20 m/s2 and feels no appreciable air resistance. When it has reached a height of 575 m , its engines suddenly fail so that the only force acting on it is now gravity. Part A What is the maximum height this rocket will reach above the launch pad
Answer:
Explanation:
We shall first calculate the velocity at height h = 575 m .
acceleration a = 2.2 m /s²
v² = u² + 2 a s
u is initial velocity , v is final velocity , s is height achieved
v² = 0 + 2 x 2.2 x 575
v = 50.3 m /s
After 575 m , rocket moves under free fall so g will act on it downwards
If it travels further by height H
from the relation
v² = u² - 2 g H
v = 0 , u = 50.3 m /s
H = ?
0 = 50.3² - 2 x 9.8 H
H = 129.08 m
Total height attained by rocket
= 575 + 129.08
= 704.08 m .
Electric and gravitational forces have many similar features because they follow idenitical mathematical formulas. In particular,________ in electricity plays the equivalent role of mass in gravity, while_______ , plays a role corresponding to free-fall acceleration. Because of this kinematics describing projectiles in gravity would carry over to electricity, but the main difference is that in electricity we have__________ , while in gravity mass is always positive, which means gravity is_______ , but electricity________ .
Answer:
Electric and gravitational forces have many similar features because they follow idenitical mathematical formulas. In particular, Charge in electricity plays the equivalent role of mass in gravity, while electric field, plays a role corresponding to free-fall acceleration. Because of this kinematics describing projectiles in gravity would carry over to electricity, but the main difference is that in electricity we have positive and negative charges, while in gravity mass is always positive, which means gravity is always attractive, but electricity could be attractive and repulsive.
Explanation:
The formulas of Electric and gravitational fields are as follow
Electric Field
F(electric)=kq1q2/r^2
Gravitationlal Fieeld
F(grav)=GMm/r^2
As you see both follow the inverse square law in the formula
Both of these act between two bodies without having any contact. The gravitational field acts on the mass of an object Whereas the electric field acts on the charge.
The gravitational field can only attractive while the electric field can be attractive or repulsive.
Normally electric field is stronger than the gravitational field.
In particular, Charge in electricity plays the equivalent role of mass in gravity, while electric field,
What is gravitational force?Newton's law of gravity states that each particle having mass in the universe attracts each other particle with a force known as the gravitational force.
Gravitational force is proportional to the product of the masses of the two bodies and inversely proportional to the square of their distance.
Electric and gravitational forces have many similar features because they follow identical mathematical formulas.
In particular, Charge in electricity plays the equivalent role of mass in gravity, while electric field,
Plays a role corresponding to free-fall acceleration. Because of these kinematics describing projectiles in gravity would carry over to electricity,
but the main difference is that in electricity we have positive and negative charges, while in gravity mass is always positive,
which means gravity is always attractive, but electricity could be attractive and repulsive.
Hence, in particular, Charge in electricity plays the equivalent role of mass in gravity, while electric field,
To learn more about the gravitational force refer to the link;
https://brainly.com/question/24783651
A basketball with a mass of 20 kg is accelerated with a force of 10 N. If resisting forces are ignored, what is the acceleration of the basketball?
Does fg increase or decrease when one mass increases
Answer:
It increases because fg means Force of gravity so When the mass of the two objects increases with mass and increases the distance between an object
There you go!!!
6th grade science I mark as brainliest !
2. A force of 10 N is applied to an object which accelerates at a rate of 2m/s2. What is the mass
of the object?
(10 Points)
10 kg
5 kg
2 kg
20 kg
How much force does it take to give a 70 kg object an acceleration of 20 mls2
Answer:
heyy
Explanation:how r uuu
Jojo and Roro begin side-by-side at one end of the playground. At the same moment, they begin to move toward the other end of the playground, Jojo at a constant velocity of 3.0 m/s, Roro at a constant velocity of 2.0 m/s. Sometime during her trip, Roro stops to rest for 2.0 s, but then starts again at her original constant speed. When Jojo reaches the end of the playground, she is 10 m ahead of Roro.
(a) For how much time did Roro move?
(b) How far did Roro move? (Set it up, good notation, equations in symbols first, etc.)
Answer:
Roro's total travel time = 6 seconds out of which he rested for 2 seconds
Distance covered by Roro = 8 meters
Explanation:
Given that :
Jojo:
Constant velocity, v = 3m/s
Travel time = h
Roro:
Constant velocity, v = 2m/s
Roro rest for 2 seconds
Travel time = h - 2
Recall:
Distance = speed * time
Distance covered by Jojo:
3 * h = 3h
At this distance ;
Roro's distance = 3h - 10
Using formula :
Roro's distance = 2 * (h - 2)
Hence,
2(h - 2) = 3h - 10
2h - 4 = 3h - 10
2h - 3h = - 10 + 4
-h = - 6
h = 6
Hence, Roro moved for :
h - 2 = 6 - 2 = 4seconds
Distance moved by Roro:
2(h - 2) = 2(6 - 2) = 2(4) = 8 meters
A student stretches a spring, attaches a 1.20 kg mass to it, and releases the mass from rest on a frictionless surface. The resulting oscillation has a period of 0.750 s and an amplitude of 15.0 cm. Determine the oscillation frequency, the spring constant, and the speed of the mass when it is halfway to the equilibrium position.
Answer:
the speed of the mass when it is halfway to the equilibrium position is 1.26 m/s
Explanation:
Given that;
mass of the object m = 1.20 kg
period of oscillation = 0.750 s
Amplitude ( A/x) = 15.0 cm = 0.15 m
now;
a) Determine the oscillation frequency;
oscillation frequency f = 1/T
we substitute
f = 1 / 0.750 s
f = 1.33 Hz
Therefore, the oscillation frequency is 1.33 Hz
b) Determine the spring constant;
we solve for spring constant from the following expression;
T = 2π√(m/k)
k = 4π²m / T²
so we substitute
k = (4π² × 1.20) / (0.750)²
k = 47.3741 / 0.5625
k = 84.22 N/m
Therefore, the spring constant is 84.22 N/m
c) determine the speed of the mass when it is halfway to the equilibrium position
So, at equilibrium, the energy is equal to K.E
such that;
1/2mv² = 1/2kx²
mv² = kx²
v² = kx² / m
v = √( kx²/m)
we substitute
v = √( 84.22×(0.15 m)²/ 1.2 )
v = √( 1.89495 / 1.2 )
v = √ 1.579125
v = 1.26 m/s
Therefore, the speed of the mass when it is halfway to the equilibrium position is 1.26 m/s
What inspired Ronald McNair to do science
Answer:
While working as a staff physicist at hughes Research Laboratories McNair learned that the National Aeronautics and Space Administration (NASA) was looking for scientist to join the shuttle program;)
Meandering valleylike features on the Moon's surface are called
Answer:
Meandering valley like features on the Moon's surface are called rilles
Explanation:
NOUN
rilles (plural noun)
a fissure or narrow channel on the moon's surface.
A hanging wire made of an alloy of titanium with diameter 0.05 cm is initially 2.7 m long. When a 15 kg mass is hung from it, the wire stretches an amount 1.68 cm. A mole of titanium has a mass of 48 grams, and its density is 4.54 g/cm3. Based on these experimental measurements, what is Young's modulus for this alloy of titanium
Answer:
Explanation:
Young's modulus of elasticity Y = stress / strain
stress = force / cross sectional area
= weight of 15 kg / π r²
= 15 x 9.8 / 3.14 x ( .025 x 10⁻² )²
stress = 74.9 x 10⁷ N / m²
strain = Δ L / L , Δ L is change in length and L is original length
Putting the values
strain = .0168 / 2.7 =.006222
Young's modulus of elasticity Y = 74.9 x 10⁷ / .006222
= 120.88 x 10⁹ N / m² .
A pendulum has a period of 6.98s. Calculate the length of the pendulum. Use
9.8m/s^2 for gravity. *
Answer:
Length, l = 0.126 meters.
Explanation:
Given the following data;
Period = 6.98s
Acceleration due to gravity, g = 9.8m/s²
To find the length, l;
[tex] Period, T = 2 \pi \sqrt {lg} [/tex]
Substituting into the equation, we have;
[tex] 6.98 = 2*3.142 \sqrt {l*9.8} [/tex]
[tex] 6.98 = 6.284 \sqrt {9.8l} [/tex]
[tex] \frac {6.98}{6.284} = \sqrt {9.8l} [/tex]
[tex] 1.1108 = \sqrt {9.8l} [/tex]
Taking the square of both sides
[tex] 1.1108^{2} = 9.8l [/tex]
[tex] 1.2339 = 9.8l [/tex]
[tex] l = \frac {1.2339}{9.8} [/tex]
Length, l = 0.126m.
a 90 kilogram dog runs across the dog park at a speed of 6.5 meters per second. what is the magnitude and direction of the average force required to stop the dog in .85 seconds?
Answer:
am not sure about the answer
Explanation:
you need to find out the amount of force it's going in for example 10n or 100n then you need to times it the distance then devide by the time
hmu if u brave shawtys
Answer:
BET, & done ✌
Answer:
boop
Explanation:
which is the product of cellular respiration? A. ATTP B. light C. oxygen D.sugar
The study of heat is ____?
Explanation:
thermodynamics is the study of heat.
Answer The study of heat and its relationship to useful work is called thermodynamics and involves macroscopic quantities such as pressure, temperature, and volume without regard for the molecular basis of these quantitie
Explanation:
A ball of mass 0.3 kg flies through the air at low speed, so that air resistance is negligible. (a) What is the net force acting on the ball while it is in motion
Answer:
X axis F=0
Y axis Fg = - 2.94 j ^
Explanation:
The motion of a ball in air where the air residence is indicated to be negligible can be analyzed using Newton's second law.
We set a reference system, where the x-axis is horizontal and the y-axis vertical.
X axis
There are no forces on this axis, therefore the ball goes at constant speed.
Force is zero
Y axis
In this axis it is subjected to the acceleration of gravity that creates a force equal to the weight of the body, in a vertical direction.
Fg = m g
Fg = 0.3 9.8
Fg = 2.94 N
Fg = - 2.94 j ^
the boold are vectors; negative sign indicates that the force eta directed vertically downward
Please answer the question
Answer:
Option B. 300 m/s².
Explanation:
From the question given above, the following data were obtained:
Mass (m) of student = 100 Kg
Mass (m) of ball = 1.5 Kg
Force (F) applied on the ball = 450 N
Acceleration (a) of ball =?
From Newton's 2nd law,
F = ma
Where
F => Force applied
m => mass of object
a => acceleration of object.
With the above formula, we can obtain the acceleration of the ball as follow:
Mass (m) of ball = 1.5 Kg
Force (F) applied on the ball = 450 N
Acceleration (a) of ball =?
F = ma
450 = 1.5 × a
Divide both side by 1.5
a = 450 / 1.5
a = 300 m/s²
Therefore, the acceleration of the ball is 300 m/s²
3. If the gravitational force between 2 objects is 50 N, what is the gravitational
force when the distance between the two is increased to four times the distance?
The gravitational force : 3.125 N
Further explanationGiven
F₁ = 50 N
Required
F₂
Solution
Newton's Gravity Law:
[tex]\rm F=G.\dfrac{m_1.m_2}{r^2}[/tex]
with F = gravitational force,
G = gravitational constant,
m1, m2 = mass of object,
r = distance between two objects.
The value of m and G are the same , so :
F₁ ≈ 1/r₁²
The distance between the two is increased to four times:
r₂ = 4r₁
F₂ = 1/(4r₁)²
F₂ = 1/16r₁²
F₂ = F₁ x 1/16
F₂ = 50 : 16
F₂ = 3.125 N
